Intelligence signaling apparatus



y 2, 1929- A. F. BENNETT ET AL INTELLIGENCE SIGNALING APPARATUS Filed Aug. 20, 1925 Patented July 2, 1929.

UNITED STATES 1,719,645 PATENT OFFICE.

ARTHUR F. BENNETT, OF RICHMOND HILL, NEW YORK, AN D CHARLES R. MOORE, OF

MAPLEWOOD, NEW JERSEY, ASSIGNORS T WESTERN ELECTRIC COMPANY, INCOR- PORATED, OF NEW YORK,'N. Y., A CORPORATION OF NEW YORK.

INTELLIGENCE SIGNALING APPARATUS.

Application filed August 20, 1925. Serial No. 51,278.

This invention relates to telephone trans- A microphone is mounted in the bell portion mitters and more specifically to a transmitter which is particularly well adapted for use in telephone hand sets.

For maximum transmission efiiciency hand sets of the types heretofore used required that the hand set be maintained while in operation in a substantially vertical position with a very limited range on each side 1 of the vertical. The operative position of the set was determined by the type and the disposition of the microphone in the transmitter, and any deviation from this limited range when, for example, the user moves the hand set too far from the vertical position, greatly interferes with the transmission of speech. This is due to the fact that when the set is held in certain positions a part of the carbon granules move out of contact with the plunger with the result that the carbon is not fully acted on by the vibrations of the plunger, thus impairing the transmission of speech. v

Transmitters made according to this invention entirely avoid these defects b the use of a novel arrangement of parts W ereby the hand set may be used in practically any position Without interfering in any way with efiicient and clear transmission of speech, and which will in general greatly improve the quality of the transmitter in the transmission of speech or other signals.

This and other advantages of this invention will appear from the following descrip according to the features of this inventionconsists of a metallic shell 12 provided with a partition 13 disposed in a manner to form two inverted bell portions E and B. The rim of bell portion E is inwardly threaded and fits a metallic flange which extends perpendicularly from a base of the handle 9.

B and comprises a conical shaped diaphragm 14, the base of which is adapted to rest between damping rings-15 and 16 mounted in a recess made by the provision of a cylindrical flange in a mounting plate 17. This plate has a plurality of radially disposed apertures such as 18 and 19, shown in Fig. 3 whlch have been provided for a purpose that will be hereinafter described. In the central portion of plate 17 there is provided a centrally disposed recess in which a pad of thin paper rings 21 is held in position concentric with respect to a central opening 1n the plate 17 and in engageable relation with a truncated portion of diaphragm 14 with which the pad of paper rings 21 cooperates to form a closure for the carbon granules 22. The disc 17 is provided with a central opening 20, the bounding surface of which contacts with the carbon granule and forms the innermost disposed electrode of the microphone. A cylindrical flange portion 20 of disc 17 is inwardly and outwardly threaded. The inwardly threaded portion of this flange is adapted to receive the outermost disposed electrode 24 which is insulated therefrom by means of a flanged insulating ring 26, held in adjusted position therein by means of a metallic ring 27, screwed into the inwardly threaded portion of disc 17. A plate ring 23 of insulating material is disposed between the electrodes 20 and 24 in order to form therewith a microphone of the barrier type. A disc member 28 has a th'readedengagement with electrode 24 and serves in cooperation with the insulating disc 24' to form the outwardly disposed wall for the microphone. On the disc 28 is rigidly secured a double armed tightly on the periphery of the bell portion B and in it a sound. deflecting member 31 is mounted. This sound deflecting member is disposed adjacent the opening of the mouthpiece and is adapted to cooperate therewith to form an annular air passage. The metallic screen 32 and the sound deflecting member 31 are held in the mouthpiece by means of an apertured ring 83 which like the transmitter mouthpiece may be made of any suitable insulating material. -A metallic ring 34 adj-acently mounted at the base of the diaphragm 14 but separated therefrom by the pad of damping rings 15 and insulated from the shell 12, bydneans of insulat ing strip 40 and ring 37 has a radial arm 38 which extends in engageable relation with a tightening screw 89. This screw is insulated from the partition 13 and is provided for holding the. contacting spring 46 in electrical connection with the electrode and the associated connection in the handle through the mounting plate 17 thus forming one side of the microphone electrical circuit. The other side of the microphone circuit being through the resistance varying material in contact with electrode 20, electrode v24, disc 28, the double armed member 35, the

slotted ring 29 and the transmitter shell 12 .having suitable conenction with the incoming wi're'47' and the electrical receiver 10.

By means of this arrangement the sound waves are deflected in the annular path formed by the conical member 31 and the mouth piece through the metallic screen 32, the apertured ring 33, the apertured frame supporting the oiled silk screen 44, the screen, and thence through the apertures 18," 19, etc. of mounting plate 17 to one-side ofthe diaphragm 14. But itis to be noted part in the that the initial displacement of the diaphragm is in a direction away from the resistance varying material in the microphone which greatly improves the transmission and efficiency of the transmitter. By means of this construction the hand set may be held in any position without danger of breaking the electrical circuitof the microphone since the r esistance varying material will in any position continue to bridge the two electrodes 20 and 24 through the barrier 23 and due to the resistance varying material resting on the diaphragm any sound wave impressed thereon through the air paths above traced will be faithfully reproduced at the receiver end of the line thus avoiding all the inconveniences present in telephone hand sets new in use. y

The transmitter mo'uth piece 30 may be held in adjusted position with respect to, the

longitudinal axis of the handle by means of a lock nut 43 which is screwedon the periphery of the rim'bounding the bell portion E in abutment withthe base of the handle as shown.

What is claimed is: 1. A telephone transmitter comprising a 2. A telephone transmitter comprising a granular electrode chamber, a pair of stationary electrodes insulated from each other and forming the marginal walls of said chamber, a stationary front wall forming an insulated closure for said chamber, and a diaphragm the central area of which forms a closure 'for the rear of said chamber, the

peripheral part of the same side of the diaphragm which engages the granular maalls of said terial communicating with an air passage leading to the transmitter mouthpiece.

3. A transmitter comprising a metallic shell, a conical shaped diaphragm resiliently held in adjusted position therein, a microphone element containing resistance varying material actuated by said diaphragm, a

mouthpiece, a sound deflecting device there-j in forming an annular air passage leading the pressure waves in a direction for oper ating terial. I

4. A transmitter comprising a microphone having resistance varying material therein,

said diaphragm away from said macoaxially disposedelectrodes forming the a marginal walls of said microphone, a diaphragm in contacting relation with said material, a rigid insulating disc. forming a closure of the microphone, a metallic shell for supporting said diaphragm and said electrodes in position concentric with respect to each. other, a mouthpiece in threaded engagement with the eriphery of said shell, a sound deflecting evice' cooperating with said mouthpiece whereby the displacement of the diaphragm in response to pressure waves impinged on. one side thereof at its peripheral portion is eifected) in a. direction away from the resistance varying material.

5. A transmitter comprisin shell, a microphone mounted 1n said shell, said microphone comprising co-axiall posed electrodes forming the margina wall of the chamber containing the resistance varying material, an insulating member disposed between said electrodes, a rigid member secured to one side 'of said electrode and forming a side wall forsaid chamber, a diaphra formin the other wall of, said chain er, a mout piece for-housing said microphone, and a sound deflecting device cooperating with said mouthpiece to form an annular air path for operating said diaphragm to loosen said material upon the dis-' ioo a metallic impinging of pressure waves on one sideof the diaphragm.

crophone having co-axial electrodes the marginal walls of the granule chamber, carbon granules in, said chamber, a diaphragm disposed in contacting relation with the carbon granules and adapted to form the rear wall of said chamber, a solid disc having one of its plane surfaces insulated from the carbon and adapted to form the front wall of said chamber, and a contacting device secured to said disc adapted to form one terminal of the microphone circuit.

7. In a transmitter, a supporting metallic shell having a central partition, a microphone mounted on one side of said partition, a diaphragm disposed adjacently to said partition and arranged to form a wall for. the microphone, a plurality of damping rings associated with said diaphragm for holding the resistance varying material in said microphone, a mouthpiece secured to the periphery of said shell, a sound deflecting device in said mouthpiece adjacent the opening of said mouthpiece and forming an annular air passage for actuatin said microphone upon the impinging 0 pressure waves on the peripheral portion of said diaphragm.

8. In a transmitter, a microphone having resistance varying material and a diaphragm arranged to form a wall for the microphone, a pluralit of damping rings associated with said diaphragm for holding the resistance varying material in said microphone, a lurality of damping rin s disposed at t e periphery of said diap ragm, a mouthpiece for said transmitter, and a sound deflecting device cooperating with the mouthpiece for causing t e movement of in said microphone, a conical diaphragm having its apex in contacting relation. with said material, a sound deflecting device c0- operating with the mouthpiece to form an annular air path leading to the periphery of said diaphragm and a plurality of screen protectors across said air path.

10. A transmitter mounting having a threaded flange extending perpendicularly to the base of the mounting, the transmitter having a .mouth piece, a shell having threaded portions for engaging said flange and the mouth piece, and a screw threaded ring of insulating material engaging said shell. for securing said mouth piece in adj usted position with respect to the mounting.

11. A telephone transmitter comprising a granular electrode chamber, a pair of stationary electrodes insulated from each other and forming the marginal Walls of said chamber, one of said electrodes having a central portion forming the front supporting wall of said chamber, and a diaphragm the central area of which forms a closure for the rear of said chamber.

In witness whereof, we hereunto subscribe ournames this 7th day of August A. D.,

ARTHUR F. BENNETT. CHARLES R. MOORE. 

